Diagnosis, analysis, opinions needed to solve trailer sway

weldingisfun · Jul 4, 2012

Okay guys and gals, your help is needed.

Just bought an old, home built, livestock trailer (pic attached). It is 5 X 10 feet, single axle. Looks to have 5000 lb leaf springs on it (pics attached).

On the ride to our place there was a very pronounced sway beginning at 55 mph. My truck is a 3/4 ton Dodge Ram and the sway could be felt in my steering. The trailer has no floor, right now, and is very light weight. I set the hitch ball on the truck as low as possible to put more weight on the trailer tongue, but the sway was still very pronounced.

The trailer has car tires on it so I imagine the soft sidewalls probably contributed to the swaying.

My intent is to fix it up and sell it, but that sway must be eliminated.

Please give me your diagnosis, analysis, and/or opinions to solve the trailer sway problem. Thanks, in advance, to all who are willing to contribute.

rasimmo · Jul 4, 2012

The axle is set too far forward. It appears to be centered on the box. I am not sure on the correct percentages, but you need more in front of the axle than behind. I built a 6x12 recently. I measured a couple that I had access to and decided to put the axle 7' from the front of the trailer(not including the tongue). That worked out good on mine.

Diamondpilot · Jul 4, 2012

That is a 3,500# axle, 5 lug. 5,200# and 6,000# axles are 6 lug.

The axle is too far forward like Rasimmo said. 60/40 is the normal split. My take on it is sell it as is and let it be somebody's problem who is not you. Its a lot to bite off to fix and there will be no room for profit.

Live and learn.

Chris

JPRambo · Jul 4, 2012

fix it up like you said is your intent. Buy a truck bed tool box in a yard sale and put it on the tongue. That should add tongue weight to help eliminate the sway.

bcp · Jul 4, 2012

Make it a 5x9

I wish Photoshop made a welder to modify things as easily as images.

Bruce

Artisan · Jul 4, 2012

Well...if the axle needs to go aft, instead of movin' the axle hows about just
cuttin' a foot or so off the back O da trailer? Maybe put on some "like" properly
rated tires too. Also if you weigh it, you are prob not far off the 3500 deal.
Have a big guy grab the trailer and try to move it side to side while
you watch the springs, if they move cut everything off and add new,
BUT, you should cut your losses, sell it for what your in it and build one and
sell it, IMO. Yep, it is too tall too, I bet ya in the past good ole
boys have loaded her to the brim w/ ROCKs.

Todd727 · Jul 7, 2012

Years ago, I bought a large equipment trailer. Trailered home empty just fine. Loaded it up and it was all over the road. As I was moving and didn't have time to unload, I hooked up a sway control. Headed out and everything was fine. About 500 miles down the road, it blew a tire. Decided to bite the bullet and put four new tires on it. Started thinking about it, disconnected the sway control and found out that the real problem was caused by crap tires.

If you want to do a little trouble shooting, put some weight in the front of that trailer and see if it does better.

Finally, it might be easier to extend the tongue than move the axle.

Your tires look worse than mine did.

jejeosborne · Jul 7, 2012

It looks like the axle placement is back beyond the halfway point which is good. The light weight compared to its height might be your problem. The wind load on the front is causing a light tongue weight. The front is acting as a sail and lifting the tongue. Since you enjoy welding, I would move the axle back as far as possible within the fenders, lay a heavy floor and you may be fine. 10-15% tongue weight is what you want. I would shoot for 15% with that profile. May also try to open the front of the trailer with some mesh or something to allow the wind through.
Jeff

TO_Bud · Jul 7, 2012

I would also check the "springs to frame" connections. There are probably cheap plastic bushing in there that are worn through, and the bolts may also be worn down.

Bigfoot62 · Jul 7, 2012

Diamondpilot said:
That is a 3,500# axle, 5 lug. 5,200# and 6,000# axles are 6 lug.

The axle is too far forward like Rasimmo said. 60/40 is the normal split. My take on it is sell it as is and let it be somebody's problem who is not you. Its a lot to bite off to fix and there will be no room for profit.

Live and learn.

Chris

I think Chris nailed it.
But, if you insist on keeping it, add another axle behind the one you have. Tandem axles will probably fix it.

weldingisfun · Jul 8, 2012

More to chew on. Having read all of your input I was ready to shorten the trailer by 12 inches. I agree that moving the axle would be to much work and trouble.

One thing I failed to mention at the beginning was the floorboards had been removed from the trailer (Rear). I am thinking that added to the swaying, but here is what really contributed to the problem. Whoever built this thing was really into building for strength. The gate consisted of two parts; the first part is hinged to swing out (Gate). The gate is build from angle and flat stock all of it 5/16" thick. The gate, as seen in Pic 2, weighs at least 125 pounds. Inside the gate, he added a lift gate (Lift Gate) which I first thought was made from 3/4" OD round pipe. Wrong! It is 3/4" solid round stock. It has to weigh between 75 to 80 pounds.

Once I had removed the gates, I took the trailer back out on the road and it never even tried to sway, even at 65 mph.

I do intend to replace the car tires with trailer tires and the gate will be replaced with a new one built from 14 guage square and rectangular tubing.

For TO-Bud, the spring bushings are definitely not plastic or even nylon. They are steel with grease fittings. Those springs are definitely "Old School".

Thanks for everyone's input. If you are interested, I will post pictures of the completed rebuild. Once finished, I hope to be able to sell it for 1200 and $1400.

westcliffe01 · Jul 8, 2012

Honestly, moving the axle is no big deal. Buy some new hangers and bolts from Etrailer.com Just make sure the bolts and width matches the springs you have now. A set for a single axle should run about $20 Suspension Kit Single-Axle Trailer Suspension | etrailer.com

You want to be sure that with a load in the box and possible inclination, that a suitable load is maintained on the ball.

rasimmo · Jul 8, 2012

When you put the gate back on,even a lighter one, the sway will come back. You need to put more weight in front of the axle. In my opinion the easiest way is to move the axle back. That is pretty easy to do. A lot easier than cutting down the back of the trailer then reinforcing it so it won't flop around. Just measure from the hitch and make sure it is square so it will track straight.

JDgreen227 · Jul 8, 2012

K7LN said:
With a new gate and a floor, the sway may not reappear, or it probably will appear at a different speed. It's going to be trail and error. Different tires or remove some of the top weight might help too. Personally, I'd try the tool box idea suggested in post #4. Maybe the original owner never worried (or knew) about the sway because it was always used on back roads at 45.

Guys, not to be critical of the suggestions to add a toolbox to the tongue, but it looks rather short for installing one. Attachment below shows the toolbox on my 6X12 utility trailer, I had to use a 12" deep truckbox as a deeper one would hit the rear bumper of my truck during sharp turns. You need a minimum of at least 28 inches, preferably more, from the coupler centerline to the front of the truck toolbox. I had 22 inches of space when I originally installed a standard depth truckbox on mine and the front of the box touched the rear bumper a few times when I was backing up.

roamerr · Jul 8, 2012

2 words is all you need to know -- TONGUE WEIGHT. Add some weight on the tongue and it will track true. 10% of the load on the tongue should work. If the tongue is light I have seen 300 lb trailers make a Dodge Ram 3500 dually dance.

Diamondpilot · Jul 8, 2012

roamerr said:
2 words is all you need to know -- TONGUE WEIGHT. Add some weight on the tongue and it will track true. 10% of the load on the tongue should work. If the tongue is light I have seen 300 lb trailers make a Dodge Ram 3500 dually dance.

That and bad tires or rims. I have a 18' car hauler and it would dance my F-350 diesel around when empty but loaded it did fine. Long story short I was on my way to pick up a Corvette for a guy and was early so I stopped in a tire shop to have my tires balanced. I bought the trailer new and the tires were not balanced from the factory. It made a night and day difference plus they discovered one of my wheels was bent. Not sure if I bent it or it was bent from the get go. The installed my spare for me and less than $20 I was on my way with a smooth ride.

I called the dealer and they sold me a new wheel for $18 plus shipping and the tire store swapped it out and balanced it for free.

Chris

weldingisfun · Aug 25, 2012

The rebuild is finished and, as promised, I am sending along pictures.
Thanks to everyone offering assistance. The trailer pulls now at 70 mph without any sway. This is what it took to accomplish it:
Twelve inches was cut off the tail end of the trailer.
The swing-out and center lift-gates were replaced with gates made from square tubing. The estimated weight reduction is approximately 100 pounds.
Time involved to make it all happen was about 40 hours.

It is now for sale for $1200. We will see how that goes with this economy.

JDgreen227 · Aug 25, 2012

Enjoyed the pictures and appreciate the follow-up to the original post...thanks for doing that because I have thought now and then about the thread and wondered what your final solution was. Keep us posted on what you sell the rig for !!! NICE JOB...:thumbsup: